Powertrain, generic (extended)

P2596 Turbocharger Speed Sensor B Circuit High

Check engine lightOn
EmissionsRelevant
Drive cycleNot required
Limp modePossible

With P2596 the engine computer sees the line of turbocharger speed sensor B sitting above its valid window - the usual pattern for a signal shorted to supply voltage, an interrupted ground or a defective sensor output. The code was added to Bentley's W12 speed-sensor bulletin in its later revision (2053348/10, December 2022), which also brought in the Bentayga; it is handled like the low fault: work through the wiring checks including a short to B+, and if they pass, fit a new sensor for the affected bank and report back if the fault returns. P2595 is the low-voltage counterpart, P2594 a wrong but electrically valid speed, and P2581 the same fault on sensor A. Expect the warning lamp and possibly reduced boost.

Likely causes

Signal wire of sensor B shorted to supply or battery voltage
Interrupted ground of sensor B
Defective output stage of speed sensor B

Symptoms

  • Malfunction indicator lamp on
  • Implausibly high speed for the second turbo in live data
  • Possible boost reduction

Repair estimate

DifficultyHardWorkshop job
Parts and labour€100–1,200
Time1–8 h

Typical range across vehicles; the real cost depends on what the testing finds.

Parts involved

turbo speed sensor bsensor wiring

Related codes

P2593P2594P2595P2597P2581

References: static.nhtsa.gov, law.cornell.edu.